Lathe



(No Model.) 3 Sheets-Sheet 1.

P. M. STEVENS & O. E. MOORE.

LATHE.

No. 280,259. Patented June 26, 1883.

l yibwssa: F atgpggtors:

I r0] vens 2% [g CharlesE.M0ore, I I y MMw/filborney 3 Sheets-Sheet 2.

F. M. STEVENS & 0. E. MOORE. LATHE.

No. 280,259. Patented June Z6, 1883.

(No Model.)

, Inveniors: I'ramkfl l'. Stevens;

Witnesses:

. 01 19 1}. Moore,

w. #6 by Q/WJWW UNITED STATES PATENT OFFICE.

FRANK M. STEVENS AND CHARLES MOORE,,OF BOSTON, MASSACHUSETTS; SAID MOOREASSIGNOR TO SAID STEVENS.

LATHE.

SPECIFICATION forming part-of Letters Patent No. 280,259, 'dated June26, 1883,

Application filed January 4, 1883. (No model.)

To (ZZZ whom it may concern Be it known that we, FRANK M. STEvENs andCHARLES E. MooEE, both of Boston, in

the county of Suffolk and State of Massa- 5 chusetts, have jointlyinvented certain new and useful Improvements in Lathes, of which thefollowing, taken in connection with the accompanying drawings, is aspecification. 7 Our invention relates to a lathe for turning iirregular forms, and to that class of such lathes in which the desiredform is produced by the automatic movement of the cutting toolcontrolled by a patterircam attached to the arbor or revolving spindleof the lathe.

i It may be employed in producing avariety of work, but is especiallydesigned for backing off the teeth of rotary cutters,-or, in otherwords, in producing the necessary clearance required by the teeth ofsuch circular revolving cutters; and it consists in certain arrangementsand combinations of mechanism, which will be best understood byreference to the description of the drawings and the claims to behereinafter given.

' In the drawings, Figure 1 is a plan of a lathe embodying ourinvention. Fig. 2 is an elevation of the same. Fig. 3 is a transversesection on line w w on Figs. 1 and 2, looking'toward the tail-stock.Fig. 4 is a transverse section on line a: x on Figs. 1 and 2, lookingtoward the head-stock. Fig. 5 is a partial section on line 3/ g; onFigs. 1 and 2, looking toward the headstock. Fig. 6 is a section on line2 z on Fig. 5. Fig. 7 is a partial section, showing 3 5 the end of thehead-stock spindle, the patterncam, and the arbor for holding the work.Fig. 8 is an end view of said spindle. Fig. 9 is an elevation of saidarbor for holding the work. v

o A is the bed, havingcast therewith or secured upon it the headstock Band tail-stock O. In the bearings B and B of the headstock 13 is mountedthe spindle D, having secured upon it, between said bearings, the

' wornrwheel E,which is revolved by means of the worm F, secured uponthe shaft F and engaging with the teeth ofthe worm-wheel E. TheWorm-shaft F is located with its axis at right angles to that of thespindle D, and is arranged to revolve in bearings F and F secured to thebed A by screws to a, as in Fig. 2. The shaft F extends through thebearing F, and has secured upon its end outside of said bearing thecone-pulley G arranged to be driven by asuitablebelt. (Not shown.) Theopposite end of said shaft F does not extend through the bearing F, butbears against a vdisk or washer, b, in said bearing, which serves totake the end-thrust of the shaft in that direction, while it isprevented from slipping in the opposite direction by the collar a,secured upon it in contact with the inner end of the bearing F. A cap,(Z, screwed upon the hub of the bearing B serves to take the end-thrustof the spindle D, and also as a means of efi'ecting a slight endwiseadjustment of the same in a well-known manner. The end of the spindle Dopposite to the cap (I is provided with an enlarged portion, 6, andafiange,

f, as shown in Fig. 7, and carries the patterncam II, made in the formof a ring accurately fittin g over the enlarged portion 0, and securedto the flange f by screws 9 9, Fig. 4.

I is an arbor for holding the work, it being supported at one end by theback center, J, and having its opposite end made conical and fitted to asimilarly-shaped recess in the end of the spindle D. (See Fig. 7.) Thearbor I is provided with two cars, 71 72, extending at right angles tothe axis thereof, and adapted to fit the groove 6 in the enlarged end 0of the spindle D, by which arrangement the arbor I is caused to revolvewith said spindle. Two screws, h h, pass through the ears 71 71, and arescrewed into the enlarged portion 0, thus serving to hold the arbor I inposition when the back center, J, is withdrawn for the purpose ofplacing the work upon or, removing it from the arbor I. The work to beturned or the cutter to be backed off (shown in dotted lines 0 at j inFig 5,) is placed upon the arbor I between the collars t i, andheld'firmly in place a by means of the nut t in a well-known manner.

The tail-stock G is of ordinary construction, the back center, J, beingcarried by the spindle 9 5 I J, which is advanced or withdrawui by ascrew (not shown) operated by the handle J" The bearing for the spindleJ has a longitudinal split or cut in its rear side, and is provided witha clamping-screw having a handle, J for too M. The slide M is fitted toa dovetail, Z, upon the bed A, and is adapted to be adjustedlongitudinally thereon, or in a line parallel to the axis of the spindleD, by means of the screw N engaging with the nut m, which projects downward from the under side of the slide M through an opening, m, in thetop of the bed A. .The screw N extends to the right-hand endof the bedA, and, passing through the same, has secured upon its outer endthehand-wheel N, by means of which it may be operated. It is of reduceddiameter where it passes through the hub of said handwheel and the endof the bed, thus forming a shoulder upon the inside, whilethe hub of thehand-wheel forms another shoulder upon the outside, to prevent saidscrew N from slipping endwise. The slide M is provided with a dovetailupon its upper side, to which is fitted the slide L, adapted to move ina direction at right angles to the axis of the spindle D, and having adovetailed groove in the front portion of its upper side, in which isfitted the slide K, adapted to be moved or adjusted in a.

parallel direction with the slide L by means of the screw 0 engagingwith the nut O, which is a portion of the slide L, and provided with thehand-wheel O, for the purpose of operating the same. The screw Q has abearing in the car it, projecting downward from the front end of theslide K, the hand-wheel 0 upon the outside and the shoulder a upon theinside of said ear causing the slide to move with said screw. The slideK carries a tool-post, P, in the slot of which the cuttingtool k issecurely held by the set-screw P, in the usual way. The slides K, L, andM are provided with suitable gibs, adjusted by screws in the ordinarymanner. The slide Lis arranged to be moved automatically, as will now bedescribed. In the slide M, near its rear end, is mounted the rock shaftQ, upon one end of which is secured the lever B, extending upward andcurving toward the front of the machine near its upper end, which isforked, and has secured therein by the bolt q and nut q ahardened-steelcontact-point, r, whichbears against the outer edge of the pattern-camH, it being held against said cam by the action of the spring S, securedat its lower end to the end of the slide M and pressing at its upper endupon the lever B, as shown.

In a recess in the slide M is located a lever, T, secured firmly uponthe rock-shaft Q near the middle of its length, and connected with theslide L by means of the link U, engaging at one end with the pin 8 inthe forked upper end of the lever T and at the other end with the pin 8,set in the ears t 25, formed upon the rear end of the slide L.

The edge of the cam H is shaped with reference to the form which it isdesired to give to the work to be turned, and as each throw of said campasses beneath the point r it will act, through the medium of the leverB, rock- 'shaft Q, lever T, and link U, to draw the slide L, andconsequently the cutting-tool 7c, toward the work, the reverse motionbeing effected by the action of the spring S. As arranged for backingoff rotary cutters, the shape of the cam H is somewhat similar to thatof a ratchet-wheel, the number of throws necessarily corresponding withthe number of teeth in the critter, and the shape of the edge of thecutting-tool should conform exactly to the longitudinal shape of thecuttingedges of said teeth. The transverse adjustment of thecutting-tool to regulate the depth of cut is readily effected byoperating the hand' wheel O and the longitudinal adjustment by means ofthe hand-wheel N, as previously set forth.

It will be seen that the slide L may be operated by the lever B withoutthe interposition of the rock-shaft Q and lever T, as by a slightmodification in the shape of said slide L or lever R the link Umaybemade to connect them directly together; also, that the contact surfaceor point r at the end of the lever B may be of a different shape, or itmay consist of a small anti-friction roll.

We have shown an arbor, I, of special construction for convenience inholding a certain class of work but it is obvious that various kinds ofwork may be centered or held in different ways without affecting theoperative principle of the machine.

A great advantage is obtained by using the worm F and worm-wheel E as ameans of imparting rotary motion to the spindle D, and through it to thework to be acted upon, over a machine in which the power is applied bymeans of a belt upon a pulley secured directly to the spindle, assometimes practiced, or a volve very slowly, but positively. This it isdifficult, to say the least, to insure in the case of the spindle beingdriven by a belt acting directly upon a driving-pulley mounted upon thespindle. The use of the back gears on the headstock of the latheobviates this difficulty, and is all that is necessary in doing ordinarylathe-work, such as turning shafting or other circular work when acontinuous chip is cut; but in doing such work as this machine isdesigned to do-namely, making several distinct and separate cuts to eachrevolution of the spindle-thereis much more liability of the toolchattering, and thus making imperfect cuts, than with. the worm andworm-wheel arranged as herein described, owing to the backlash, socalled, in the gear-teeth.

What we claim as new, and'desire to secure by Letters Patent of theUnited States, is

1. The spindle D, provided with the enlarged portion e and the fiangefand having the ring-cam H detachably.secured thereto, substantially asand for the purposes described. t p

2. The combination of the spindle D, having secured thereon thepattern-cam H and the worm-wheel E, the springactuated lever B, providedwith a contact-surface to rest upon said cam, the slide L, carrying thetool-postP, means of connecting'the slide L and lever B, the worm F andmeans of imparting rotary motion thereto, and means of holding the workand causing it to revolve with the spindleD, substantially as and forthe purposes described.

3. The spindle D, provided at its inner end with the flange f, andhaving a transverse groove, 6, cut across its inner" end face, as setforth, in combination with the arbor I, pro- Vided with the ears h h,and means of center ing said arbor and securing thereon the work 20 tobe actedupon, substantially as and for the purposes described.

In testimony whereof we have signed'our names to this specification, inthe presence of two subscribing witnesses, 011 this 2d day of 25January, A. D. 1883.

FRANK M. STEVENS. CHARLES E. MOORE.

